OOOOOOOOOOOOOOOOOH!!!! Finally, I feel so accomplished for contributing something! (To one of my favorite wad authors even!)
I was a bit sick of how riders and SRB2CB did it (yeah, remember that old skateboard or whatever that went pretty much unused by the community and didn't even have proper slope physics? Pepperidge Farm remembers...) where no matter what angle you were going up or down, you'd go the same speed unless you held down and even then that only slowed you down a little, and since slopes AND lua happened, I've been really stoked to see someone make something better, and you've nailed it!
Edit: Did you impliment a brake? Like if you hold backwards does it slow you down?